Place the potato in a large saucepan and cover with plenty of cold water. Place over high heat and bring to the boil. Cook, covered, for 8 minutes or until tender. Rinse under cold running water. Drain well.

Step 2

Meanwhile, cook the asparagus in a medium saucepan of salted boiling water for 2-3 minutes or until bright green and tender crisp. Refresh under cold running water. Drain well.

Step 3

Use a fork to whisk together the mayonnaise, buttermilk, peppercorns, vinegar and dill in a bowl until well combined. Taste and season with salt and pepper.

Step 4

Place the potato, asparagus and rocket in a large serving bowl and gently toss until just combined. Drizzle with the mayonnaise mixture and serve immediately.

Note: You can prepare this salad to the end of step 3 up to 1 day ahead. Store in separate airtight containers in the fridge. Continue from step 4 just before serving.